The high percentage of energy consumption by fossil fuels in the building sector in combination with climate change across the globe increased the need to move into more sustainable building ...practices. Thus, the integration of sustainable strategies and active solar energy systems into the design process is becoming a tool for the reduction of the energy demand and improvement of the energy performance of existing and new buildings.
This study investigates the energy performance of an existing residential apartment building in Limassol, Cyprus before and after its energy renovation, using a double skin façade combined with building integration of active solar energy systems. The proposed research starts with the analysis of the existing building energy performance, focusing on the energy loads for cooling, heating, and artificial lighting. Subsequently, the results of the existing situation are evaluated using digital energy simulations, and the process moves on to the renovation and energy upgrade of the building by integrating the aforementioned systems. Energy-Plus simulations are performed where the proposed systems’ contribution to the energy reduction is investigated including their energy reduction potential. The before and after simulations are compared, with the focus to prove whether the systems can be viable in terms of decreasing the energy demands of the building. Finally, a life cycle cost (LCC) analysis is performed, to determine the viability of the enterprise. The performed research proves that the application of the double façade, consisting of three main features — a building integrated photovoltaic system (BIPV), glazing system and rambling planting, can combine the positive effects of each individual system, if there is a combined systematic approach on the architectural design of the building envelope. The combination of the above led to a reduction of 83.5% in the energy consumption of the building, from 94,321 kWh of the existing situation to the 15,563 kWh of the proposed one. This reduction includes the contribution from BIPV system, which amounts to 26,706 kWh/ year of primary energy — thus covering the 63% of the proposed consumption of the building. On the other hand, the LCC analysis sums that a careful combination of bioclimatic design and active solar systems, can have a viable payback period, which in this case is 13 years.
The overall aim of this research is to determine whether the use of a double skin façade combined with integrated active solar systems constitute an energy and cost-efficient solution for the viable refurbishment of an existing building in the south-eastern Mediterranean area.
Energy performance of buildings directive sets a goal to achieve a highly energy efficient and decarbonised building stock by 2050. In this study, a pilot nZEB (nearly zero energy building) ...renovation of an existing apartment building is analysed. nZEB criteria of new apartment buildings was set as the energy performance target in designing renovation solutions. The whole building envelope was additionally insulated with prefabricated modular panels and new service systems were installed. Measured energy consumption after the renovation showed that the pilot building fulfilled the minimum energy performance requirements for new apartment buildings, but nZEB target was not achieved. Measured heating energy consumption is 1.6 times higher (mainly because of the higher indoor temperature, supply air temperature, window airing, and higher ventilation airflow rates which methodology for heating energy calculations are not taken into account) and measured energy need for DHW is 4.4 times higher (mainly because of the real use profiles as well unexpected performance of solar collector and sewerage heat recovery system) than expected in building design. Results show that in renovation projects (also in new projects), occupant behaviour and the real use of building should be used as more realistic input parameters for designing energy performance. Distribution and circulation losses of air handling units, heating coils and DHW (domestic hot water) systems should be taken into account in the national energy calculation methodologies as service system heat losses can be a significant part of energy consumption at nZEB levels. If the renovated building would be used according to design methodology, the nZEB target can be achieved.
•Performance gap between measured and designed primary energy consumption is 34%.•Heating energy consumption increase 29% is related with user behaviour.•Heat losses of DHW circulation system are 20% from DHW energy use.•DHW circulation losses should include to primary energy calculation.
We performed the first large-scale investigation of indoor air quality (IAQ), energy and occupant behavior and satisfaction, in 650 energy-efficient dwellings in western Switzerland. The ...investigation included comparative assessment of 217 green-certified Minergie (M) and 433 energy-renovated (R) dwellings. Data were collected through a combination of questionnaire survey of building characteristics and occupancy symptoms/satisfaction, as well as field measurements of radon, total volatile organic compounds (TVOC), formaldehyde and fungi. The results showed that 90% of M dwellings relied on renewable and low-carbon energy sources for space and water heating, as compared to only 40% of R dwellings. The annual electricity consumptions of M and R dwellings were similar (~33 kWh/m2), however, R dwellings consumed more gas and heating oil, thus contributing more to greenhouse gas emissions. Concentration of sampled air pollutants in the two dwelling types was generally below the maximum guideline values. Interestingly, concentration of all air pollutants was significantly lower in M relative to R dwellings: Radon (48 vs. 91 Bq/m3), TVOC (167 vs. 259 μg/m3), formaldehyde (12 vs. 15 μg/m3) and fungal colony forming units (33 vs. 48 CFUs). Statistical comparisons revealed that residents of naturally ventilated R dwellings tended to open window more frequently, while occupants of M dwellings relied on mechanical ventilation. We found no differences in occupant satisfaction and self-reported symptoms between the two dwelling types. The findings of this study are of potential utility for interpreting impacts of growing building energy renovation initiatives on indoor air quality, ventilation design and occupant satisfaction.
•The first Swiss large-scale survey of Minergie (M) and energy-renovated (R) houses.•M dwellings relied more on renewable and low-carbon energy sources than R dwellings.•Radon, TVOC, formaldehyde and fungi were generally low, especially in M dwellings.•Ventilation habit varied in M and R dwellings, while owner satisfaction was similar.•Occupants of M and R dwellings reported similar incidences of health symptoms.
•Energy saving potential in historic wooden apartment buildings is up to 63%.•In historic wooden apartment buildings an economically viable energy saving level is 50%.•The largest energy saving ...potential lies in heat source and building service systems.•Of the building structures, insulation of the external wall has the highest potential.•New heating and ventilation systems must be installed to fulfill regulations limits.
Buildings represent the largest sector of primary energy consumption and play a major role in saving energy and reducing greenhouse gas emissions. Our analysis of energy consumption and potential energy savings is based on field measurements, computer simulations and economic calculations. The average primary energy consumption (PE) of wooden apartment buildings was 331kWh/(m2a) 83% higher than the limit 180kWh/(m2a) set in national regulations for apartment buildings subject to major renovation. The studied buildings represent a high potential for energy savings. The renovation packages were compiled using different insulation measures, HVAC solutions and energy sources to achieve a 20–65% reduction of primary energy. For historic buildings, the renovation solutions that concentrate on the building envelope can be problematic due to the need to preserve cultural and architectural values. Our calculation results indicate that the cost optimal PE level is around 250kWh/(m2a) and the point at which renovation packages recover expenses is around a PE level of 170kWh/(m2a). In terms of the architectural appearance the point at which renovation packages recover expenses is around a PE level of 210kWh/(m2a). We propose to set a different PE limit for historic wooden apartment buildings with an architectural appearance worth preserving.
Climate change is one of the greatest challenges facing the building sector and rural areas in particular should be prioritised due to their special characteristics. In this work, ways to adapt rural ...residential buildings in a Mediterranean climate to climate change via energy renovation were studied, taking La Rioja (Spain) as a case study. Different energy renovation solutions were evaluated under different climate change scenarios considering the possible evolution of the climate zones. The energy and economic impacts of these energy-renovated buildings were compared to those of existing buildings. Nearly zero-energy buildings were achieved by changing the thermal envelopes and their corresponding interior partitions. The study discovered that, on the one hand, the heating energy demand was reduced while the cooling energy demand was increased, thus reducing the total energy demand; on the other hand, the best energy renovation solution entails compliance by nearly zero-energy buildings with current building thermal regulation for the current climate zone. This work can serve as a guide to establish and promote energy renovation policies that are effective in addressing climate change and are economically viable. Furthermore, the methodology developed and the results obtained can be extrapolated to other cold Mediterranean climate zones.
•The energy and economic impacts associated with the adaptation of rural buildings to climate change were evaluated.•The different climate change scenarios accounted for the possible evolution of the climate zones.•Total energy demand will be reduced as cooling energy demand increases less than heating energy demand decreases.•The NZEBs that meet the current thermal building regulation are the best energy renovation solutions.•This work can serve as a guide for the energy renovation of rural Mediterranean residential buildings.
To avoid health risks and discomfort, the European Energy Performance for Building Directive (EPBD) mandates that “Member States should support energy performance upgrades of existing buildings that ...contribute to achieving a healthy indoor environment.” There is, however, no widely accepted method for rating the overall level of indoor environmental quality (IEQ), although several different approaches are proposed by standards, guidelines, and certification schemes. To fill this void, a new classification rating scheme called TAIL was developed to rate IEQ in offices and hotels undergoing deep energy renovation during their normal use; the scheme is a part of the energy certification method developed by the EU ALDREN project. The TAIL scheme standardizes rating of the quality of the thermal (T) environment, acoustic (A) environment, indoor air (I), and luminous (L) environment, and by using these ratings, it provides a rating of the overall level of IEQ. Twelve parameters are rated by measurements, modelling, and observation to provide the input to the overall rating of IEQ. Their quality levels are determined primarily using Standard EN-16798-1 and World Health Organization (WHO) air quality guidelines and are expressed by colours and Roman numerals to improve communication. The TAIL rating was shown to discriminate IEQ levels when its feasibility was examined in eleven buildings across Europe to provide support for its applicability and input for further modifications. Opportunities for using the scheme in other types of buildings and for its further development and application are discussed.
The most recent regulations, as well as the scientific studies, remark the importance of the evaluation of the entire life cycle on building renovations, relative to the environmental impact and ...economic feasibility, making the Life Cycle Assessment (LCA) the prioritizing analysis. The objective of the study is to develop a simplified methodology for the environmental and economic assessment of residential building renovations with life cycle approach. For this, a script-based tool-kit is developed: the first tool optimizes the thickness of envelope insulation based strategies; the second tool is for the prioritization of strategies by assessing their environmental performance and economic feasibility. In order to follow the objective, the development of the two tools is presented: both tools follow a parallel scheme where the input parameters are required by an excel file and the calculation script provides the results automatically by exporting the results excel file. The evaluation provides the quantification of the relative environmental improvement with the net energy ratio (NER), and the economic feasibility by the financial indicator of internal rate of return (IRR). The tool-kit is applied in a case study of a multifamily residential building. The results show, on the one hand, that the usability of the tool-kit can be determinant in the decision-making of stakeholders; and in the other hand, the importance of carrying out a dynamic assessment, taking into account the variation of the results caused by the uncertain parameters that differ in time. Moreover, the tool-kit can assist the development of cost-effective decarbonisation strategies.
Display omitted
•An enviro-economic assessment simplified tool-kit is provided based in LCA.•The prioritization indicators (NER, IRR) allow the relative assessment of strategies.•The optimization tool provide the optimal improvements and economic feasibility.•Dynamic assessments are necessary to cover the uncertainty of parameters.•The tool-kit is provided in open source script, applicable to other programmes.
The non-residential building stock in Germany, as in many other countries, is not fully represented in any official statistics, in contrast to residential buildings. This is surprising given the ...economic significance of this asset and its importance as a source of greenhouse gases. The knowledge gap was closed in a representative sample survey providing statistically valid data on structural parameters and energy-related characteristics of the non-residential building stock in Germany. This became possible because by December 2014 authoritative building polygons from all German cadastres were available in a national database for the first time. These geospatial data, adjusted for topological inconsistencies and supplemented with owner information in an on-site screening, were used as a sampling frame in the previously unknown population of the non-residential buildings, a new approach in building stock statistics worldwide. While the geometry of all buildings can be derived from the geospatial data, energy-related characteristics and renovation activities have to be obtained by interviews with the owners of the relevant non-residential buildings in the sample. With this methodology, regular monitoring of building stocks at reasonable costs becomes possible. It also can be transferred to other states with similar geospatial data infrastructure, in particular to other EU Member States.
•A representative sample survey was carried out in the NRBS in Germany.•Authoritative cadastral geodata was used as a sampling frame.•Structural parameters of the NRBS were quantified.•Modernization rates of building components were determined.•The methodology is a model for other EU Member States.
Climate change mitigation measures linked to households’ energy consumption have huge greenhouse gases (GHG) emission reduction potential and positive impact on energy poverty reduction. However, ...measures such as renovation of residential buildings or installation of micro generation technologies based on renewable energy sources have not realized their full energy saving and GHG emission reduction potentials, due to the energy efficiency paradox and other barriers. These climate change mitigation policies targeting the households’ sector can deliver extra benefits such as energy poverty reduction and implementation of the energy justice principle; therefore, they require more attention of scholars and policy makers. The aim of this paper is to analyze the energy poverty and climate change mitigation issues in EU households based on a systematic literature review, and to provide future research paths and policy recommendations. Based on the systematic literature review, this paper develops an integrated framework for addressing energy poverty, just carbon free energy transition and climate change mitigation issues in the EU. Additionally, we argue that more targeted climate change policies and measures are necessary in the light of the shortcomings of current measures to reduce energy poverty and realize climate change mitigation potential linked to energy consumption in households.
PDF
